When a user wishes to send a message from a mobile device that he or she has composed, such as an electronic mail (“e-mail”) message for example, the user will typically provide some input to the mobile device through the user interface of a messaging application in order to initiate the processing of the message for sending. For instance, the user may select a “send” button or menu option to send the message. Once this selection is made, users generally expect that unless an error message is generated and displayed to them immediately, the message will automatically be sent with no further input or other user intervention required.
When a message is sent by a user that is to be encoded using a secure messaging protocol, such as the Secure Multiple Internet Mail Extensions (“S/MIME”) protocol, or the Pretty Good Privacy™ (PGP) protocol or a variant thereof for example, a number of processing actions may need to take place before the message can actually be sent to its intended destination. For example, it may be necessary for the messaging application to request an update of a security policy from a policy engine (e.g. as implemented in a PGP Universal Server). This security policy dictates the particular encoding that is to be applied to a message. As a further example, it may be necessary for the messaging application to obtain an S/MIME certificate or a PGP key from a local store or a remote server before a message is encoded and sent. It may also be necessary for the messaging application to verify the status of a particular S/MIME certificate before the message is encoded and sent.
Should the messaging application encounter any problems when performing the processing actions for a message or require further input from the user before it can complete the processing of the message for sending, the mobile device may prompt the user for additional information or prompt the user to make a decision as to what should be done with the message. For example, if the messaging application is unable to verify the status of a certain certificate required to encode a message, the user may be asked to decide whether the message should be sent without encoding.
Unfortunately, it may take some time after the user initiates the processing of the message for sending before a problem is identified. Meanwhile, the user may have assumed that the message would be sent, and consequently, the user may no longer be paying attention to the mobile device. In particular, the user may have placed the mobile device into a belt holster, in a cradle, or in some other location (e.g. left on a desk), such that the mobile device is left unattended. In those cases, the user may not be aware that additional input is required before the mobile device will actually send the message.